Each map below represents the direct component of the monthly radiation received on a plane always facing the sun for 2006 year in kWh / m². There is one card per month as well as a map for the annual irradiation and animation for the year.
a) Average solar radiation in France on 2006 year in kWh / m².year:

b) Solar radiation month by month in kWh / m².mois:

2ieme loading the card is a bit long because it is near 2 Mo.
The maps were calculated from observations made by meteorological satellites according to Heliosat-2 method. The original data is stored in the HelioClim-2 database. Shading was added to maps to represent the relief.
Source: Copyright Ecole des Mines de Paris / Armines 2007
ps: the satellite method should give the IR radiation from the ground, notice the radiative forcage of the Parisian metropolis ...